Many various electronic apparatuses are provided in a car. For distributing electric power from an electric power source to the various electronic apparatuses, an electric connection box is arranged in the car. The electric connection box, which is configured to have one of various structures, is applied for that and for example, the electric connection shown in Patent Document 1 is configured to distribute by using a metal core board.
As shown in FIG. 25, the electric connection box 510, which applies a core metal plate 502 of a metal core board 501 for not only dissipating heat but also performing as a part of an electric power distributing circuit, is well-known. The electric connection box 510 distributing electric power from a battery and an alternator to electronic apparatuses includes the metal core board 501, a plurality of electronic components mounted on a surface of the metal core board 501, a connector 507a connected to the battery, a connector 507b connected to the alternator and a not-shown case receiving the above.
The metal core board 501 is provided with the core metal plate 502, insulation layers 504a, 504b covering the core metal plate 502 and conductive circuits 505 arranged at each of surfaces of the insulation layers 504a, 405b. The conductive circuit 505 is made of copper foil.
The above-mentioned connector 507a includes an L-shaped terminal 571a and a connector housing 570a. The terminal 571a includes a first connecting portion 572a to be connected with a connector of a wiring harness connected to the battery and a second connecting portion 573a mounted at the metal core board 501. The first connecting portion 572a is arranged inside the connector housing 570a. The second connecting portion 573a is joined to the metal core circuit board 501 so as to pass through the metal core board 501 and be connected electrically to the conductive circuit 505 and be insulated from the core metal plate 502.
The above-mentioned connector 507b includes an L-shaped terminal 571b and a connector housing 570b. The terminal 571b includes a first connecting portion 572b to be connected with a connector of a wiring harness connected to the alternator and a second connecting portion 573b mounted at the metal core board 501. The first connecting portion 572b is arranged inside the connector housing 570b. The second connecting portion 573b is joined to the metal core circuit board 501 so as to pass through the metal core board 501 and be connected electrically to the conductive circuit 505 and the core metal plate 502.
As mentioned above, in the electric connection box 510, the electric power distributing circuit for distributing the electric power from the battery is structured by only the conductive circuit 505 arranged at each of the surfaces of the insulation layers 504a, 504b, and a power distributing circuit for distributing the electric power from the alternator is structured by the conductive circuit 505 and the core metal plate 502. According to such power distributing circuit for distributing the electric power from the battery, thickness of the conductive circuit 505 is thinner than thickness of the core metal plate 502, so that correspondingly, larger surface area is required, and thereby it is problem that the metal core circuit board 510 becomes larger.
As a solution for the problem, according to an electric connection box 610 as shown in FIG. 26, a line-shaped slit 603 is formed at a core metal plate 602 of a metal core board 601 so as to divide the core metal plate 602 to two separate plates 602a, 602b, and one of the separate plates 602a is used for distributing electric power from the battery, and the other one of the separate plates 602b is used for distributing electric power from the alternator. Thereby, increasing a size of the metal core board 601 may be limited.
In FIG. 26, insulation layers 604a, 604b, which fill the slit 603 and cover the surface of the core metal plate 602 so as to form the two divided core metal plates 602 integrally, are shown. In FIG. 26, the conductive circuit 605 arranged at each of the surfaces of the insulating layers 604a, 604b are shown. In FIG. 26, the connector 570a connected to the battery is shown as same as FIG. 25. In FIG. 26, the connector 570b connected to the alternator is shown as same as FIG. 25.